It worked once or twice then I started cleaning up and now it can't get to work anymore. I tried to move it into the document and to the preamble. I also change the numbering and title of the part, but I don't know if that would influence it.

Thank you very much. I eventually included it before every part, because I place a different picture on every page. (My next aim will to add some js to show the time at the bottom of each frame -- LOL).
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LouisAug 3 '12 at 8:15